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Comments on ''Geranylgeraniol--a new potential therapeutic approach to bisphosphonate associated osteonecrosis of the jaw" by Ziebart T et al. (2011).
No full texttherapeutic approach to bisphosphonate associated osteonecrosis of the jaw’’ in Oral Oncology, by Ziebart T et al., and would like to compare and discuss these results with our recently published data.1 The design of the two studies is very similar: natural isoprenoids have been used to revert the mevalonate pathway inhibition induced by amino-bisphosphonates (N-BPs). Isoprenoid compounds are hypothesized to enter the mevalonate pathway after the N-BPs block, being metabolized as farnesyl-pyrophosphate and bypass the biochemical inhibition mediate by N-BPs on farnesyl- pyrophosphate synthase, restoring the metabolites flux along the pathway.2,3 Ziebart T. et al. empathized that the isoprenoid geranylgeraniol (GGOH) can antagonize the effects of N-BPs in the processes of osteoclast formation, apoptosis, bone resorption and in tumor cells (i.e. prostate cancer cells, human myeloma cells) as previously described in several studies,4,5 suggesting a therapeutic use of GGOH in bisphosphonate associated osteonecrosis of the jaw (BP-ONJ). Recently, our group demonstrated that GGOH and several other isoprenoids (farnesol, geranygeraiol, mentol, limonene) are able to revert the pro-inflammatory effect induced by the combination of N-BPs and bacterial lipoplyshaccaride (LPS) or muramyldipeptide (MDP) both in Balb/c mice and in human and murine monocytes. 2,3,6 We also proposed isoprenoid compounds as eligible treatment for the rare and still orphan disease mevalonate kinase deficiency (MKD, OMIM: 251170), characterized by genetic defect in the second enzyme of the mevalonate pathway. All this considered we would like to discuss the following issues: – We do agree with Ziebart T. et al.1 about the anti-N-BPs effect of geraniol, emphasizing that this effect is not dependent on the N-BP used on the isoprenoids. Ziebart’ group used ibandronate, pamidronate and zoledronate in their model, whereas we treated Balb/c mice and monocytes with alendronate or pamidronate obtaining comparable and reproducible findings. 2,7 Moreover geranylgeraniol, farnesol, menthol and limonene showed a comparable effect in contrasting N-BP action in our models,3 suggesting a common mechanism of action for these compounds in the context of NBP inhibition. – It is interesting to note that GGOH is able to contrast N-BP effect independently of the cellular model implied (osteoblast or monocytes) and the different outcome of N-BP inhibition. Since the block of the mevalonate pathway affects the prenylation of several signalling molecules involved in cell cycle, differentiation and cell response to extracellular stimulus, probably it results in different defects depending on the cell types. – We suggest Ziebart T. et al.1, to test other isoprenoids in addition to GGOH, such as geraniol, farnesol, menthol or limonene, in order to identify the most effective isoprenoids to treat in combination within aminobisphosphonate associated osteonecrosis of the jaw. While the dose/effect of the isoprenoid is comparable within Ziebart T. et al. and our models, additionally we would like to emphasize the importance of the timing in isoprenoid administration. – In our animal model the isoprenoid timing necessary to revert the pro-inflammatory action of alendronate or pamidronate was the critical point, because the isoprenoid must be injected the day before and/or after the N-BP.2,7 – Recently we showed that farnesyltransferase inhibitor (FTI) such as manumycin A, Tipifarnib or Lonafarnib, currently used in clinical trials as anticancer drugs, were able to contrast N-BP effect leading to a redistribution of mevalonate intermediates along its pathway.6 We propose Ziebart T. et al. to evaluate the effects of these pharmacological agents which could be an alternative therapeutic approach in the case of N-BP-induced osteonecrosis of the jaw. In summary, we do agree with the study by Ziebart T. et al., and emphasize the pivotal role of isoprenoid to rescue the phenotype inflammation induced by aminobisphosphonate treatment
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Preventing GBS neonatal desease with intrapartum prophylaxis: a retrospective study to detect its use in case of unknown colonization status
No full textBackground: Group B streptococcus (GBS) is the leading cause of neonatal morbidity and mortality in developed countries. This study aims primarily to estimate the prevalence of maternal GBS positivity and secondarily to evaluate the compliance and the effectiveness of the current GBS prevention protocol. Methods: This retrospective study has considered 27382 single pregnancies carried to delivery between 2001 and 2014 at our Obstetrics and Gynecology clinic. All women carrying a singleton pregnancy in the considered period were eligible to be included in this study. Results: The GBS swab was positive in 17.66% of cases, negative in 51.93%, and unknown in 30.41%. Data collected revealed that out of the total of GBS-positive women, 3362 were treated with antibiotic prophylaxis, and 1331 were not. There were no differences between cases admitted to NICU (neonatal intensive care unit) and perinatal deaths between treated and non-treated GBS-positive pregnancies. Moreover, the data showed that 74.62% of patients between 34 and 37 weeks of gestation at the time of delivery were treated with antibiotic prophylaxis unnecessarily, and 25.38% of patients 37 weeks of gestation whose GBS status at delivery was unknown would have required intrapartum antibiotic prophylaxis. The only risk factor for chorioamnionitis among GBS-positive women in multivariate logistic regression analysis was an early gestational age (OR 0.61; CI.95 0.56 - 0.66; p<0.05). Conclusions: GBS prevalence was found to be 17.66%, and prophylaxis in colonized patients was carried out correctly according to our internal procedure allowing a low incidence of adverse outcomes. Finally, the only risk factor associated with chorioamnionitis in GBS patients was early gestational age at delivery
Pediatric patients with inflammatory bowel disease exhibit increased serum levels of proinflammatory cytokines and chemokines, but decreased circulating levels of macrophage inhibitory protein-1β, interleukin-2 and interleukin-17
Full text linkInflammatory bowel disease (IBD) is a chronic and progressive inflammatory condition of the gastrointestinal tract. Although the causative events that lead to the onset of IBD are yet to be fully elucidated, deregulation of immune and inflammatory mechanisms are hypothesized to significantly contribute to this disorder. Since the onset of IBD is often during infancy, in the present study, the serum values of a large panel of cytokines and chemokines in pediatric patients (<18 years; n=26) were compared with age-matched controls (n=37). While elevations in the serum level of several proinflammatory and immune regulating cytokines were confirmed, such as interleukin (IL)-1β, IL-5, IL-7, interferon (IFN)-γ-inducible protein-10, IL-16, cutaneous T-cell-attracting chemokine, leukemia inhibitory factor, monokine induced by γ-IFN, IFN-α2 and IFN-γ, notably decreased levels of IL-2, IL-17 and macrophage inhibitory protein-1β were also observed. Therefore, while a number of proinflammatory cytokines exhibit increased levels in IBD patients, pediatric IBD patients may also exhibit certain aspects of a reduced immunological response
Intrauterine fetal death in a COVID positive pregnant woman
No full text: SARS-CoV-2 disease mechanisms are not yet fully understood, especially in cases affecting pregnant women. In fact, although they suffer from the same symptoms as non-pregnant women, they are more susceptible to adverse outcomes of COVID-19 as well as pregnancy complications leading to stillbirth, premature rupture of membrane, or intrauterine fetal demise (IUFD). The consequences on pregnancy are not clearly correlated with the severity of the infection. We present a case of fetal death in a 30-year-old woman with a confirmed SARS-CoV-2 infection without any other significant clinical or obstetric disorders. A histopathological examination of the placenta indicated massive and diffuse intervillar fibrinoid deposits associated with chronic histiocytic intervillositis that can be associated with SARS-CoV-2 placentitis. Given the high rates of SARS-CoV-2 infections in pregnancy, it is important to understand the factors that determine negative pregnancy outcomes, regardless of the severity of the patient's symptoms
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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